/Engine/Plugins/Runtime/MeshModelingToolset/Source/ModelingComponents/Public/Mechanics/PolyLassoMarqueeMechanic.h
Utility function clients can use to clean up poly-lasso if it is not closed (perhaps should be folded into mechanic behavior)
static bool ApproximateSelfClipPolyline ( [TArray](API\Runtime\Core\Containers\TArray)< FVector2D > & Polyline )